The RollerGirls are popular enough in Jacksonville to have many fans. These attended the Duval Derby Dames and the River City Rat Pack game at the Mandarin Skate Station on May 16.

Off the flat track, they work as nurses, pharmacists, teachers, business owners and hair stylists.

But when they don their quad roller skates, racy costumes, helmets, knee pads and fishnet tights, the action can be fast and bruising.

"It's a blast," said Melissa Ludington, a teacher who's been doing roller derby for 3? years and whose nickname is "Deviant Behavior."

She was the announcer at last weekend's match between the Duval Derby Dames and the River City Rat Pack at the Mandarin Skate Station, 3641 Kori Road. The bout, won by the Rat Pack, was mainly to prepare the teams to play other leagues and to raise money for the All-Stars' out-of-town trips, Ludington said.

Founded in March 2006, the Jacksonville RollerGirls are comprised of more than 70 skaters and have three home teams: River City Rat Pack, Duval Derby Dames and First Coast Fatales. The New Jax City Rollers, of which Ludington is a member, is the All-Star traveling team. As an All-Star, she's already played in Tallahassee and will be going to New Orleans, San Antonio and Huntsville, Ala., this year.

"You've got all these girls coming from all these different backgrounds and careers, and we've formed a sisterhood," said Ludington, who is the league's vice president.

The next game is 6 p.m. Saturday, June 19, when the Derby Dames, the RollerGirls' B team, will play Tallahassee's B team, Jail Break Betties at the Skate Station. The second game at 7 p.m. pits the City Rollers against Tallahassee's Capital Punishment. Tickets are $10 in advance or $12 at the door.

Roller derby has elements of several sports. One player on each team is the "jammer," whose goal is to skate around the ring as many times as possible without getting knocked down or out of bounds. The remaining players - three blockers led by a pivot - protect the jammer and clear her a path. Blocking is done with the hips, torso, shoulders and arms above the elbow. Points are earned for jammer laps.

In October, the RollerGirls, who are member-owned and operated, were accepted into the Women's Flat Track Derby Associationapprenticeship program, Ludington said.

The league, which also practices at the Skate Station, is known for its volunteer efforts. It supports and raises money for such charities as Toys for Tots, First Coast Crime Stoppers and the Susan G. Komen Race for the Cure.